Effects of gestation and birth weight on the growth and development of very low birthweight small for gestational age infants: a matched group comparison.

AIMS: To investigate the effects of small for gestational age (SGA) in very low birthweight (VLBW) infants on growth and development until the fifth year of life. METHODS: VLBW (< 1500 g) infants, selected from a prospective study, were classified as SGA (n = 115) on the basis of birth weight below the 10th percentile for gestational age and were compared with two groups of appropriate for gestational age (AGA) infants matched according to birth weight (AGA-BW; n = 115) or gestation at birth (AGA-GA; n = 115). Prenatal, perinatal, and postnatal risk factors were recorded, and duration and intensity of treatment were computed from daily assessments. Body weight, length, and head circumference were measured at birth, five and 20 months (corrected for prematurity), and at 56 months. General development was assessed at five and 20 months with the Griffiths scale of babies abilities, and cognitive development at 56 months with the Columbia mental maturity scales, a vocabulary (AWST) and language comprehension test (LSVTA). RESULTS: Significant group differences were found in complications (pregnancy, birth, and neonatal), parity, and multiple birth rate. The AGA-GA group showed most satisfactory growth up to 56 months, with both the AGA-BW and SGA groups lagging behind. The AGA-GA group also scored significantly more highly on all developmental and cognitive tests than the other groups. Developmental test results were similar for the SGA and AGA-BW groups at five and 20 months, but AGA-BW infants (lowest gestation) had lower scores on performance intelligence quotient and language comprehension at 56 months than the SGA group. When prenatal and neonatal complications, parity, and multiple birth were accounted for, group differences in growth remained, but differences in cognitive outcome disappeared after five months. CONCLUSIONS: Being underweight and with a short gestation (SGA and VLBW) leads to poor weight gain and head growth in infancy but does not result in poorer growth than in infants of the same birth weight but shorter gestation (AGA-BW) in the long term. SGA is related to early developmental delay and later language problems; however, neonatal complications may have a larger detrimental effect on long term cognitive development of VLBW infants than whether they are born SGA or AGA.

[Premature rupture of fetal membranes, risk of infection and infant prognosis--a comparison of 2 regions]. / Der vorzeitige Blasensprung, das Infektionsrisiko und die kindliche Prognose--Zwei Regionen im Vergleich.

The question to be answered was: Does premature rupture of membranes (PROM) and duration of PROM lead to increased mortality, neonatal and late morbidity and adverse cognitive developmental outcome? We present data of a bi-national cohort observation study in South Bavaria (SBy) and South Finland (SF). The sample included all children, who were admitted to a children's hospital (SBy N: 7505/70,600 live births; SF N: 1536/15,618), and some not transferred control infants (916 and 658, respectively). Obstetric details like PROM were obtained from perinatal records. Mortality and neonatal morbidity were recorded prospectively. Somatic, neurological and cognitive development was assessed at five and 20 months (corrected age), and final diagnosis of cerebral palsy (CP) and severe mental retardation was made at 56 months of age. Data were analysed separately for three gestational groups (< 32 (I), 32-36 (II), and > 36 weeks PMA (III)). PROM occurred more frequent in SBy than in SF and in both areas with preterm delivery. PROM irrespective of its duration had no adverse effect on mortality, morbidity, CP-rate or cognitive outcome of groups I and III in either SBy or SF. There was even a slightly lower mortality rate in extremely preterm infants after PROM. In SBy only, group II with PROM > 24 hours had a slightly increased incidence of CP. Unfavorable outcome was closely related to perinatal infections, which increased with duration of PROM. PROM and/or preterm labor occurred more often without than with inflammations of amnion and placenta. We conclude: PROM per se has no adverse effects on longterm outcome of special care infants, but it is closely associated with the developmental risk factors perinatal infections and, in particular, preterm birth. The prevention of ascending infections deserves further investigation, although such action may be beneficial lately to only a minority of individuals.

An epidemiologic longitudinal study of sleeping problems and feeding experience of preterm and term children in southern Finland: comparison with a southern German population sample.

OBJECTIVE: To determine the influence of breast-feeding on the prevalence and persistence of sleeping problems in southern Finland (SF) and southern Germany (SG). DESIGN: Prospective binational population study of infants admitted to special care units (SCUs) in geographically defined areas in SF and SG. SUBJECTS: In SF, the number of SCU infants was 1057 (very preterm, 47; preterm, 258; term, 752); 485 term infants were control subjects. In SG, the number of SCU infants was 4427 (very preterm, 284; preterm, 1419; term, 2724). MAIN OUTCOME MEASURE: Parent reports of child sleeping problems at 5, 20, and 56 months of age. RESULTS: Night waking at 5 months of age was less frequent for SCU very preterm (25.5%), preterm (40.6%), and term infants (48%) than for term control subjects (56.7% to 59.9%) in SF. No differences in sleeping behavior according to gestation were found at 20 and 56 months. Sleeping problems were greater in SF infants (25.5% to 48%) than in SG infants (15.1% to 19.1%) at 5 months of age and were explained by a higher rate of breast-feeding in SF. Breast-feeding had no long-term effects on night waking or on co-sleeping in SF. In contrast, breast-fed infants continued to wake more often in SG. CONCLUSIONS: Breast-feeding rather than gestational age is strongly related to night waking. More support for dealing with night waking might prevent early termination of breast-feeding.

The incidence of sleeping problems in preterm and fullterm infants discharged from neonatal special care units: an epidemiological longitudinal study.

Anecdotal reports have suggested that sleeping problems are a frequent complaint from parents of preterm infants. This prospective epidemiological study examined the incidence and stability of sleeping problems of very preterm (< 32 weeks gestation at birth), preterm (32-36 weeks gestation) and fullterm infants, all admitted to special care baby units (SCBU) after birth, in comparison to healthy term infants over the first 5 years of life. Preterm infants were found to have fewer and shorter night-wakings at 5 months. No differences in sleeping behaviour compared with healthy term children were found at 20 and 56 months of age. Similar significant, and moderate, stability of nightwaking from one age to the next were found for exSCBU-graduates and healthy fullterm infants. Parental interventions such as staying with the child until sleep and taking the infant into bed af night were related to nightwaking problems and increased parental distress. It is concluded that prematurity, and thus neurological immaturity and special care experience are less important than caretaking behaviour in the development of sleeping problems in both preterm and fullterm infants.

The cognitive outcome of very preterm infants may be poorer than often reported: an empirical investigation of how methodological issues make a big difference.

The effects of relying on outmoded IQ-test norms and the use of arbitrary classifications of developmental delay on estimates of cognitive impairment of very preterm infants (VPI) was evaluated in a prospective population study. Cognitive assessments included the Griffiths test at 5 and 20 months and the Columbia Mental Maturity Scales (CMM) and a vocabulary test (Aktiver Wortschatz Test, AWST) at 56 months of age. Rates of cognitive impairment of 321 very preterm infants (VPI; < 32 weeks gestation or < 1500 g birth weight) were determined according to the published test norms, to scores of a full-term control group (FC n = 321), and to scores from a representative sample of children (NC n = 431) of the same birth cohort. IQ-scores were higher in the FC and NC children than in the original standardisation sample (SS). Using the concurrent test norms (FC, NC) up to 2.4 times more VPI were identified as seriously impaired (<-2 SD) than if the published (outdated) norms were used. Serious developmental delay was underestimated when arbitrary (e.g. DQ < 70) rather than across age comparable definitions (DQ <-2 SD) were used. VPI study drop-outs had mothers with lower educational qualifications and poorer cognitive developmental scores at 5 or 20 months of age. In conclusion, a lack of appropriate control groups and use of arbitrary criteria for judging serious delay leads to large underestimations of cognitive impairment in VPI. Findings from previous uncontrolled studies of VPI need re-interpretation.

[Incidence and persistence of problems at sleep onset and sleep continuation in the preschool period: results of a prospective study of a representative sample in Bavaria]. / Häufigkeit und Persistenz von Ein- und Durchschlafproblemen im Vorschulalter: Ergebnisse einer prospektiven Untersuchung an einer repräsentativen Stichprobe in Bayern.

The prevalence and persistence of sleeping problems was studied in a prospective investigation of a representative sample of 432 German children at the ages of 5, 20 and 56 months. 21.5% of children had night waking problems at 5 months, 21.8% at 20 months and 13.3% at 56 months. Falling asleep difficulties were diagnosed in 12.1% of 4-5 year olds. One in four of five year-olds slept regularly in the bed with the parents (co-sleeping). Children with night waking problems had a 2.2 to 2.5 fold increased risk to remain nightwakers from one assessment point to the next compared with non-wakers. 7 to 14% of parents were distressed by their children's sleeping behaviour. Parental behaviour often contributed to continued sleeping problems because the children were not supported in acquiring appropriate skills to settle to sleep unaided. A developmental model for the treatment of sleeping problems is discussed.

Expanding M NET: lessons from the development of a referring physician computer network.

M NET, the University of Michigan Medical Center's statewide referring physician computer network, was implemented as a pilot project in 1990. After three years of design, development and implementation, M NET has progressed from its pilot project status to a production system within the institution's strategic plan for hospital networking. This paper describes the evolution of M NET from a small pilot project to its current production status encompassing all clinical departments and hundreds of physicians across the state. The lessons learned from the pilot, the requirements of both the referring physicians and the Medical Center, and the development of a flexible and robust network architecture to allow network expansion are addressed.

Stroke volume and left ventricular output in preterm infants with patent ductus arteriosus.

To assess the effect of patent ductus arteriosus (PDA) on left ventricular output (LVO) we studied stroke volume (SV), LVO, and heart rate (HR) in 21 very low birth wt preterm neonates with clinically symptomatic PDA before and after surgical ligation. Six additional infants were also studied before PDA with left-to-right shunt was detectable by the pulsed Doppler technique. Gestational age (median and range) was 28 (24-32) wk. SV was measured by duplex Doppler and M-mode echocardiography, and LVO was calculated as product of SV and HR. LVO was 419 (305-562) mL/min/kg during symptomatic PDA. It decreased to 246 (191-292) mL/min/kg after ligation (n = 21, p less than 0.001). SV was 2.69 (1.98-4.10) mL/kg during symptomatic PDA decreasing to 1.63 (1.22-1.98) mL/kg after ductal closure (n = 21, p less than 0.001). HR did not change after ductal closure. In the six infants with three examinations, LVO and SV were normal before detectable ductal left-to-right shunt and after ligation, but LVO was increased by 59.5 +/- 23% (mean +/- SD) (p less than 0.05), and SV by 60 +/- 32% (p less than 0.05) during symptomatic PDA. In conclusion, preterm neonates with RDS, requiring mechanical ventilation, increased LVO during symptomatic PDA by increasing their SV, and not by changing their HR.

Effectiveness of neonatal transport systems.

In order to assess the effectiveness of neonatal transport systems, morbidity on admission and early neonatal mortality of low birth weight infants below 2000 gm were studied. All infants referred to a neonatal department in Munich or Southern Bavaria from 1979 to 1981 were included. The data of infants born in Munich perinatal centers were compared to those of infants delivered in hospitals in the Munich area (radius 30 km) and in other hospitals in Southern Bavaria. Ninety-four percent of 248 LBW neonates born in the Munich perinatal centers, 87.5% of 736 infants and 84.4% of 681 LBW infants from the Munich area and Southern Bavaria respectively survived the first week of life although the morbidity risks of inborn infants were higher than those of the outborn. The presence of a pediatrician at birth and during neonatal transport to an NICU did not improve survival rates of infants delivered outside the perinatal centers. The effectiveness of neonatal transport systems is limited. They should be complemented by a maternal transport system, i.e., an infant transport in utero for cases in which the necessity for intensive neonatal care is expected.

Contributions of red cells and plasma to blood viscosity in preterm and full-term infants and adults.

In preterm infants, plasma and red blood cells display several specific properties (eg, RBC size, plasma composition) that could influence blood flow behavior. Hemorheologic properties of blood from 20 preterm infants (24 to 36 weeks of gestation), ten full-term neonates, and ten adults were studied by means of a cone-plate viscometer adapted with a Couette-type chamber allowing viscometry at a wide range of shear rates (1.15 to 230/s). Blood viscosity (at given hematocrit of 60%), plasma viscosity, and RBC aggregation were very low in the smallest preterm infants, increased with gestational age, and reached the highest values in the adults. Whole blood viscosity increased directly with increasing plasma viscosity, plasma fibrinogen, and total plasma protein concentration, with the strongest correlations at the lowest shear rate of 1.15/s. The viscosity of RBCs suspended in a nonaggregating buffer solution was similar in all groups, thereby indicating that RBC deformability is similar in preterm infants, full-term neonates, and adults. Because mixing of neonatal and adult blood components occurs in most small preterm infants as a result of the transfusion of adult blood products, viscosities of cross suspensions (neonatal RBCs in adult plasma and adult RBCs in neonatal plasma) were measured. The exchange of neonatal plasma for adult plasma increased blood viscosity values in the neonates to adult values. On the other hand, the exchange of neonatal RBCs for adult RBCs did not affect blood viscosity. These results indicate that viscosity of blood with given hematocrit is lower in preterm infants than in term neonates and adults as a result of low plasma viscosity and low RBC aggregation, and that neonatal RBCs do not possess specific properties that influence blood viscosity.

[Infant mortality- course, causes, improvement possibilities]. / Säuglingssterblichkeit - Verlauf, Ursachen, Verbesserungsmöglichkeiten.

According to national mortality statistics and to epidemiologic surveys main causes of infant mortality are congenital malformations, prematurity with its immaturity related morbidity, asphyxia, and, more recently, the sudden infant death syndrome. In all these situations the full scale of possible preventive measures has not been exhausted. This applies, in particular, to disorders in the perinatal period. What is needed is a greater awareness of risks, more gynecological interest in the baby and better teamwork between gynecologist and pediatrician; this also means a more effective use of available resources. Infant mortality rate still could be reduced by 50 percent.

The effect of moderate hypoxaemia on cardiac performance in the newborn during anaesthesia and surgery - experimental studies in newborn and two-week-old piglets.

Circulatory adaptation to hypoxaemia was studied under anaesthetic and surgical conditions in 10 newborn (age 8-42 h, weight 850-1800 g) and 8 two-week-old piglets (12-16 days, 1400-3600 g). Arterial PO2 was lowered from 60-100 mmHg to 30-40 mmHg by reducing FiO2 (concentration of oxygen during inspiration) at otherwise constant conditions; control studies were performed under the same standard conditions maintaining normoxaemia during the whole experiment in 8 newborn and 8 two-week-old piglets of comparable weight. In both hypoxic groups a prompt compensatory, statistically significant increase of cardiac performance defined by aortic blood pressure, cardiac output, peak aortic flow, stroke volume and cardiac power appeared within a few minutes of hypoxaemia, reaching a maximum half an hour later. Thereafter cardiac performance decreased steadily leading to cardiac failure. Newborns survived 197 +/- 96 min and two-week-old animals 172 +/- 128 min. Peripheral vascular resistance decreased significantly at the time of compensatory increase of cardiac performance, but increased subsequently to a maximum shortly before cardiac failure. Compensatory increase of cardiac performance was more distinct in newborn than in two-week-old piglets. Heart rate increased steadily during exposure to hypoxaemia in both groups reaching a maximum 110 min later and falling back to pre-experimental levels at the end of study. The newborn normoxic controls tolerated the experimental model significantly longer (461 +/- 167 min; P less than 0.001) than the newborn hypoxic piglets. Their response pattern, however, was basically similar. Increase of cardiac performance reached its maximum not before 130 min after the end of the pre-experimental period with subsequent fatal decrease of cardiac performance leading to cardiac failure. Two-week-old normoxic control animals responded qualitatively identically compared with the two-week-old hypoxic animals. Despite normoxaemia their average survival time did not differ significantly (209 +/- 86 min). In all four groups severe metabolic acidosis appeared in most instances during the study, irrespective of hypoxaemia or normoxaemia. Failure of stress tolerance depended on the decrease of pH per hour. This relation was more distinct in normoxic animals. In both hypoxic groups survival time correlated well with the increase of heart rate during hypoxaemia (R = 0.71 in newborn, P less than 0.05; R = 0.86 in two-week-old piglets, P less than 0.01, respectively). This correlation could not be found in the normoxic piglets.

Blood volume in newborn piglets: effects of time of natural cord rupture, intra-uterine growth retardation, asphyxia, and prostaglandin-induced prematurity.

Blood volume (BV), red cell mass (RCM; Cr-51) and plasma volume (125I-labeled albumin) were measured in 205 piglets from 28 litters shortly after birth. Spontaneous cord rupture in healthy piglets occurred during delivery (n = 25) or within 190 sec of birth (n = 82). Spontaneous and induced delay of cord rupture resulted in a time-dependent increase in BV and RCM. BV (x +/- S.D.) at birth was 72.5 +/- 10.5 ml/kg (RCM, 23.6 +/- 4.6 ml/kg) in the 25 piglets with prenatal cord rupture and 110.5 +/- 12.9 ml/kg (RCM, 38.4 +/- 7.0 ml/kg) in 17 piglets with late spontaneous cord rupture. The mean blood volume of all the 107 healthy piglets with spontaneous cord rupture was 90.2 +/- 12.7 ml/kg (RCM, 30.1 +/- 4.8 ml/kg). RCM was significantly (P less than 0.05) increased in nine piglets with intra-uterine growth retardation (RCM, 35.8 +/- 11.2 ml/kg) and in 13 with metabolic acidosis but without signs of asphyxia (RCM, 35.8 +/- 6.7 ml/kg). In five piglets with cord wrapping, prenatal cord rupture, and acute asphyxia, BV (57.8 +/- 7.3 ml/kg) was significantly decreased. In five other piglets with prenatal cord rupture and acute asphyxia, BV (67.9 +/- 10.0 ml/kg) corresponded to that of the normal piglets with prenatal cord rupture. However, delay of cord rupture to 60 sec after birth did not increase BV (66.0 +/- 11.8 ml/kg) in four piglets with acute asphyxia. Forty-one premature piglets delivered 6 days before normal term had their cords ruptured prenatally or within 5 sec of birth. Their hematocrit at birth (0.337 +/- 0.028 liters/liter) was significantly decreased compared to the normal full-term piglets with corresponding time of cord rupture (0.384 +/- 0.033 liters/liter). RCM in 18 piglets with prostaglandin-induced prematurity (18.9 +/- 3.4 ml/kg) was significantly lower than in 23 piglets whose births had been induced by ovarectomy of their mother (RCM, 22.1 +/- 3.2 ml/kg).